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Triboelectric nanogenerator (TENG) for mechanical energy harvesting has been regarded as one of the most prospective energy technologies for the new era. However, inevitable material wear during triboelectrification results in output reduction and even failure of the TENG. In this work, a submillimeter‐scale superlubric TENG (SS‐TENG) is reported that enables ultra‐low friction coefficient (µ) and stable power generation. By using the micro/nano‐processing technology, the interdigital electrodes are embedded into the dielectric layer as a flat surface, on which the highly‐hydrogenated diamond‐like carbon (PLC) is deposited as the triboelectric layer to effectively reduce the friction coefficient. The frictional properties are systematically investigated at different parameters, in which a submillimeter‐scale (130 µm) superlubricity state (µ = 0.0084) is achieved at 4 N, 2 Hz and nitrogen atmosphere. Meanwhile, the SS‐TENG has a maximum power density of 3 mW m−2, which can remain stable at the superlubric condition. This work has first realized the freestanding‐mode superlubric TENG in submillimeter scale and provided a viable strategy for the development of long‐lifetime TENG, which may have great applications in frictional energy recovery from mechanical components, human joint motion, and the natural environment. [ABSTRACT FROM AUTHOR]

This study presents an intelligent soft robotic system capable of perceiving, describing, and sorting objects based on their physical properties. This work introduces a bimodal self‐powered flexible sensor (BSFS) based on the triboelectric nanogenerator and giant magnetoelastic effect. The BSFS features a simplified structure comprising a magnetoelastic conductive film and a packaged liquid metal coil. The BSFS can precisely detect and distinguish touchless and tactile models, with a response time of 10 ms. By seamlessly integrating the BSFSs into the soft fingers, this study realizes an anthropomorphic soft robotic hand with remarkable multimodal perception capabilities. The touchless signals provide valuable insights into object shape and material composition, while the tactile signals offer precise information regarding surface roughness. Utilizing a convolutional neural network (CNN), this study integrates all sensing information, resulting in an intelligent soft robotic system that accurately describes objects based on their physical properties, including materials, surface roughness, and shapes, with an accuracy rate of up to 97%. This study may lay a robotic foundation for the hardware of the general artificial intelligence with capacities to interpret and interact with the physical world, which also serves as an interface between artificial intelligence and soft robots. [ABSTRACT FROM AUTHOR]

A series of direct‐current tribovoltaic nanogenerators (TVNGs) with high current density have been developed for energy harvesting and mechanical sensing recently, but the lead wires that need to be connected to two relatively moving parts have greatly restricted the application of TVNG. Herein, a freestanding‐mode TVNG (FTVNG) is proposed based on metal, p‐type silicon (p‐Si), and n‐type silicon (n‐Si). As the freestanding part of metal simultaneously rubs against p‐Si and n‐Si, opposite direct current (DC) outputs can be generated, thus forming a DC output from p‐Si to n‐Si in the external circuit. Resulting from the distinctive structure, FTVNGs are applicable for harvesting energy from moving objects without attached wires. Additionally, by using steel needles to precisely control the actual contact area, the electrical output characteristics and influence laws of the tribovoltaic effect under different working parameters such as area and speed are studied. Moreover, FTVNG is integrated into the traditional rolling bearing as a triboelectric bearing, realizing energy recovery from the rotational motion of mechanical parts and speed sensing, which demonstrates the great application potential of TVNG in basic components and parts. [ABSTRACT FROM AUTHOR]

Tactile detection is a crucial technology in many fields, such as electronic skin, touch screen control, human prostheses, and screen fingerprint identification. Tribotronics has demonstrated active mechanosensation from external mechanical stimuli, which greatly enriches the sensing mechanisms of tactile detection. In this work, a monolithic integrated indium‐gallium‐zinc‐oxide (InGaZnO or IGZO) thin‐film transistor (TFT) array is developed for high‐resolution tactile detection. By using the conventional semiconductor fabrication processes, each IGZO TFT cell in the array shows uniform electrical performance. In addition, the drain–source current can be individually tuned by the electrostatic potential generated by the contact electrification between a movable gate and the gate dielectric. The monolithic integrated array displays a relatively high resolution of 12 pixels per inch and can realize a millimeter‐level tactile perception and motion tracking. This work presents a facile and viable strategy toward micro/nano‐scale tribotronics, which can realize high‐resolution and large‐scale tactile detection. [ABSTRACT FROM AUTHOR]

The triboelectric nanogenerator (TENG) is a new energy technology that is enabled by coupled contact electrification and electrostatic induction. The conventional TENGs are usually based on organic polymer insulator materials, which have the limitations and disadvantages of high impedance and alternating output current. Here, a tribovoltaic effect based metal–semiconductor direct‐current triboelectric nanogenerator (MSDC‐TENG) is reported. The tribovoltaic effect is facilitated by direct voltage and current by rubbing a metal/semiconductor on another semiconductor. The frictional energy released by the forming atomic bonds excites nonequilibrium carriers, which are directionally separated to form a current under the built‐in electric field. The continuous average open‐circuit voltage (10–20 mV), short‐circuit direct‐current output (10–20 µA), and low impedance characteristic (0.55–5 kΩ) of the MSDC‐TENG can be observed during relative sliding of the metal and silicon. The working parameters are systematically studied for electric output and impedance characteristics. The results reveal that faster velocity, larger pressure, and smaller area can improve the maximum power density. The internal resistance is mainly determined by the velocity and the electrical resistance of semiconductor. This work not only expands the material candidates of TENGs from organic polymers to semiconductors, but also demonstrates a tribovoltaic effect based electric energy conversion mechanism. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) have demonstrated enormous potential applications for acquiring human motion energy and ambient mechanical energy, which is the foundation of energy for the new era. However, with alternating current (AC) pulse and huge inherent impedance, the TENGs usually exhibit low‐energy supply efficiency when either powering conventional electronics or charging energy storage devices directly. Efficient power management has always been a technical bottleneck for the TENGs toward practical applications in self‐powered microsystems. Over the past years, several strategies of power management have been proposed, such as rectification, electromagnetic transformation, capacitive transformation, and direct current (DC) conversion, which can be used for voltage regulation, impedance matching, and efficiency improvement for electronics. Herein, the recent advances on power management for TENGs are systematically reviewed and analyzed, which has exhibited manageable triboelectric power by electronics as an important research issue of TENGs. Finally, the existing challenges and future perspectives in this field are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Liquid metals (LMs) have attracted great attentions in electronics for great interface contact and flowability. Here, an LM‐gated tribotronic transistor (LMTT) is demonstrated, in which an electrostatic potential is created through the triboelectrification of LM and dielectric layer, and the carrier transport between drain and source can be tuned by the swing‐induced electrostatic potential instead of the traditional gate voltage. Based on the fabricated LMTTs, an electronic gradienter is developed, which can be used for angle measurement and exhibits a great sensitivity, large sensing range, and excellent stability. This work has first introduced the LM into the tribotronic device, which may have potential applications in mechanical calibration, civil engineering, and geologic exploration. [ABSTRACT FROM AUTHOR]

Abstract: Growing demand in automobile safety system raises a requirement to electronic devices being self‐powered, stable, and durable. Herein, a self‐powered Hall vehicle sensor (SPHVS) is demonstrated for automobile safety system, which integrates the triboelectric nanogenerator, the management circuit, the magnet, and the Hall element. The tribotronic constant current source is proposed to steadily power the Hall element in rotational motion at any different speeds. Furthermore, the performances of the SPHVS for vehicle speed sensing and vehicle braking monitoring are systematically investigated, which exhibits wide sensing range, great stability, and excellent sensitivity. This work clearly proposes a promising solution for speed sensing and braking monitoring, and indicates the potential applications of power tribotronics for the self‐powered electronic devices in prospective automobile industry. [ABSTRACT FROM AUTHOR]

Tribotronics has attracted great attention as a new research field that encompasses the control and tuning of semiconductor transport by triboelectricity. Here, tribotronics is reviewed in terms of active mechanosensation and human–machine interfacing. As a fundamental unit, contact electrification field‐effect transistors are analyzed, in which the triboelectric potential can be used to control electrical transport in semiconductors. Several tribotronic functional devices have been developed for active control and information sensing, which has demonstrated triboelectricity‐controlled electronics and established active mechanosensation for the external environment. In addition, the universal triboelectric power management strategy and the triboelectric nanogenerator‐based constant sources are also reviewed, in which triboelectricity can be managed by electronics in the reverse action. With the implantation of triboelectric power management modules, the harvested triboelectricity by various kinds of human kinetic and environmental mechanical energy can be effectively managed as a power supply for self‐powered microsystems. In terms of the research prospects for interactions between triboelectricity and semiconductors, tribotronics is expected to demonstrate significant impact and potential applications in micro‐electro‐mechanical systems/nano‐electro‐mechanical systems (MEMS/NEMS), flexible electronics, robotics, wireless sensor network, and Internet of Things. [ABSTRACT FROM AUTHOR]

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